Quick coupler latch



Dec. 20, 1955 HOUGHTON 2,727,292

QUICK COUPLER LATCH Filed March 26. 1953 HOWARD 0. HOUGHTON,

1N1 'EN I OR.

United States Patent QUICK COUPLER LATCH Howard D. Houghton, Los Angeles, Calif., assignor to Marman Products Company, Inc., Los Angeles, Calif a corporation of California Application March 26, 1953, Serial No. 344,803 12 Claims. (Cl. 24-279) This invention relates to a latching assembly of the type providing for rapid coupling and uncoupling action. This type of latching assembly is particularly useful when employed in conjunction with tube couplings which unite adjacent aligned tube sections and which are frequently connected and disconnected from the tube sections.

An important object of the invention is to provide a latch assembly of a type which may be coupled and uncoupled With improved ease and rapidity.

rxZiOthfiI object is to provide a latch assembly of the T-bolt and quick-coupler latch type, which is of improved simplicity, low fabrication cost, and of weight-saving construction.

An object of especial importance is to provide a T-bolt type quick coupler latch assembly having improved positive locking characteristics such as to prevent uncoupling in the presence of rough vibration conditions.

A further object is to provide a T-bolt type quickcoupler latch assembly haw'ng means to securely hold the T-bolt against rotation, in order to (1) hold the T-bolt stationary while the nut is being tightened thereon, and (2) prevent any loosening of the threaded connection between the T-bolt and its nut (e. g. in response to vibration), to the slightest degree, when the latch assembly is in use.

Other objects and advantages will be apparent upon examination of the following specification and appended drawings in which:

Fig. l is a side elevation of a latch assembly embodying one form of the invention as incorporated in a V-band type of band clamp;

Fig. 2 is a fragmentary partially sectional plan view of the latch assembly disclosed in Fig. 1;

Fig. 3 is a longitudinal sectional view of the latch in Fig. 1;

Fig. 4 is a plan view of band clamp embodying a modied form of the invention, with parts broken away to better illustrate the same;

Fig. 5 is a side elevation of the invention as disclosed in Fig. 4;

Fig. 6 is a plan view, partly in section, of another modification;

Fig. 7 is a plan view of another modified form of the invention, with part of the latch broken away to better illustrate the invention; and

Fig. 8 is a side elevation of the invention as disclosed in Fig. 7.

The embodiment of the invention disclosed in Figs. 1, 2 and 3 is embodied in a conventional V-band type of band clamp designated generally by the numeral 2, the latch assembly being designated generally by the numeral 3. In the V-band type of clamp the clamping pressure is exerted as a result of circumferential tension in a constrictor band 4 which encircles the V-band 5, the constrictor band being preferably fixed to the V-band (e. g., as by spot welding).

The latch assembly 3 includes a quicl'ocoupler latch, designated generally by the numeral 6; and 'a latch bolt 7, which is preferably in the form of a T-bolt having a trans 2,727,292 Patented Dec. 20, 1955 verse T-head 8 and a shank 9, and provided with a nut 20. The latch 6 is fabricated as a sheet metal stamping having a web portion ll which is integral with a pair of opposed side arms 11 interconnected thereby. These side arms 11, for a majority of their length beginning at web 14 include portions 12 which diverse away from the web portion 1d (Fig. 2) and have parallel terminal portions for anchorage to one end of band 4.

The diver ent arm portions 12 are provided with elongated slots 14 which may be lanced in the blank for the latch 6 during the blanking operation thereof, the side arms and web portion being developed in a forming operation following the blanking operation. Rivet openings 15 in the terminal arm portions 13 may be pierced also in the blanking operation and are in registry for accommodating a rivet 16. The slots 14 are also in registry when viewing latch plate 6 in side elevation. The opposed longitudinal margins 17 and 18 of the slots 14 are spaced just sufficiently to permit T-head 8 to slide freely longitudinally within the slots during the latching and unlatching operations. The length of the slots 14 is largely determined by the degree of divergence of the arm portions 12 as related to the length of T-head 8.

When the T-bolt is in fully latched position as shown in Figs. 1 and 2 the extremities of the bolt head project entirely through the respective slots 14 and project beyond the respective arm portions 12, this projecting condition continuim during a major portion of the movement of the T-head 8 away from the web portion 10 until a point is reached where the transverse distance between the diverging inner walls of arm portions 12 is slightly greater the length of the bolt head. When this position is reached, the T-head 3 may be freed from the slots 14 so that the latch 6 may be swung upwardly about pivot 16. Thus the unlatching operation is completed. Relatching is of course accomplished by swinging the latch 6 back downwardly until the diverging arm portions 12 embrace the T-head 8 (as shown in dotted lines in Fig. 2).. Then the T-bolt can be drawn away from the latch 6 at the same time that the bolt head is being steered into the slots 1 It will now be apparent that after the nut 29 has been backed oil far enough on shank 7, then the latching and unlatching operation can be conducted sin ply and rapidly.

The latch assembly may be used in conjunction with a band clamp, of which one type may be the conventional V-band. The constrictor band 4, which is fixed to and encircles the V-band 5, has a loop portion 21 which receives the pivot pin 15 and is doubled back upon itself to form an end portion 22, which is welded or otherwise secured to the body of the band. The other end portion of band 4 is bifurcated and then doubled back upon itself about the head 24 of a T-trunnion 23, thereby providing a pair of spaced loop portions 25 (only one of which can be seen in Fig. l). The bifurcation slot of this end of the band together with the opening 26 (see Fig. 4) in the head of the T-trunnion 23, accommodates the shank of T-bolt 7. A cap 23 abuts the outer end of the T-sleeve, and nut 20 abuts the cap. As the nut is tightened, the head 8 of the T-bolt is drawn against the near extremities of the slots 14 and some torque is transmitted by the T-head 8 to the side arms of the lach 6. However, the web portion 19, being in proximity to the ends of the slots where the torque is applied, adequately resists any tendency of such torque to distort the latch 6.

One of the important advantages of the invention, constituting an improvement over the conventional quickcoupling T-bolt type latching assembly, is the provision for engagement of both ends of T-head S by the latch 6, in a manner such as to resist any tendency of the T-bolt to rotate (1) when the nut 26 is being tightened thereon, or (2) under the eilect of vibration to which the latch assembly may be submitted when in use. In the conventional quick-coupler latch assembly of this general type, the bolt shank extends through a notch in the end web of the latch, and it does not provide a positive means for restraining the bolt from rotation, such as that which is provided by the present invention.

When the band clamp is drawn tight, the latch 6 will engage and exert radially inward pressure against the V- band 2 at a point intermediate the pivots 16, 24, owing to the greater radial distance of T-head 8 from the axis of the band than that of pivots 16, 24. In small diameter applications the bolt may also rest on the V-band 2, and in very small-diameter couplings, the bolt may be bent to bridge the tubing curvature.

It may be noted that the diverging arm portions 12 subtend between them a dihedral angle, the median bisector plane of which is coincident with the median plane of the band clamp (a plane bisecting the band and at right angles to the band axis). Furthermore, the arms (i. e., their longitudinal axes) diverge in a common plane of the arms, to which the individual arms are normal, said plane being normal to the median plane of the band clamp, parallel to the axis thereof, and loosely speaking, tangent to the band. The longitudinal axes of slots 14 are substantially parallel to this common plane of the arms.

In the modified form of the invention disclosed in Figs. 4 and 5, the web portion 10a is made with considerable surface area for resisting torque transmitted to the side arms 12a by the bolt head 8a upon tightening of nut 2.0a. This extensive surface area, however, also provides a piloting surface for assisting in steering the bolt head 8a into the slots 14a after the latch 6a has been swung down about its pivot 16a into a position of encasing the bolt head within the confines of its divergent side walls. The latch 6a simply needs to be swung down until the underneath surface 29 of its web portion is resting against the bolt head (it being understood that the T-bolt is temporarily positioned relative to the divergent side walls so that its length is less than the distance between such divergent side walls thereby providing sufiicient clearance for the initial entry of the bolt head within the confines of the divergent side walls). With the bolt head resting against the under surface of the web portion (in the approximate position shown in dotted lines in Figs. 4 and 5), the head is unerringly steered into the opposed registered slots 14a simply by pulling the shank 9a of the bolt 7a through the T-trunnion 23a in a direction to the left when viewing Figs. 4 and 5, and at the same time maintaining contact between the bolt head and the under surface of the web, since the under surface of the web at its respective side margins forms the respective upper longitudinal margins of the slots.

Fig. 6 illustrates a modified form of the invention in which the latch of Figs. l3 is modified as viewed in plan, although in side elevation and longitudinal section it may be the same as shown in Figs. 1 and 3 respectively. It differs from the latch shown in Figs. l3 in having a relatively flat web portion 10!) disposed in a plane at right angles to the longitudinal axis of the latch, instead of the semi-cylindrical web portion 10 of Fig. 2; and further differs in having a pair of parallel side arm portions 12' disposed between the web portions 10b and the di vergent arm members 125. The parallel side arm portions 12' are adapted to embrace the bolt shank 9 fairly closely so as to restrain lateral movement of the bolt and thereby prevent any possibility of the bolt head slipping out of either of the slots 14. Otherwise, the latch 6b may be the same as, the latch 6 of Figs. 1-3.

Figs. 7 and 8 show a modification of the latch of Figs. 4 and 5, wherein the web portion 10c corresponds generally to the web 10a of Figs. 4 and 5, being disposed in a plane generally parallel to the common plane of the axes of slot 14c, but is relatively narrow in a direction parallel to the longitudinal axis of the latch instead of extending a major portion of the length of the latch as in Figs. 4, 5. Figs. 7 and 8 also illustrate how the latch may be relatively straight in the longitudinal direction rather than arcuate as shown in the other figures. In this connection, it will be understood that any of the latches of Figs. 1-6 inclusive may be either longitudinally arcuate or longitudinally straight without materially affecting the invention.

I claim:

l. A latch assembly for a band clamp including a constrictor band having means at each end for connection to respective male and female-parts of the latch assembly, said latching device comprising: a T-bolt adjustably connected to one end of the constrictor band and a latch swingably attached to the other end of the constrictor band, said latch having spaced side arms and a web portiOn bridging and integrally joining said side arms, said side arms having therein, longitudinal slots which are in substantial registry when viewing the latch in side elevation, the side arms being disposed substantially normal to the common plane of their longitudinal axes and diverging away from the free end of the latch in said common plane, the longitudinal axes of the slots being substantially parallel to said common plane, the length of the T-bolt head being greater than the minimum distance between the side arms at a point remote from said free end to provide for inserting the ends of the T-bolt head into the slots, and less than the distance between the side walls to provide for inserting the ends of the T-bolt head into the slots, at a point adjacent said free end, to provide for reception of said ends in the slots.

2. In a band clamp including a constrictor band, a latching assembly for releasably connecting the opposite ends of the band, said latching assembly comprising: a T-bolt including a shank adjustably and swingably connected to One end of the band, and a T-head on an end of said shank; and a latch swingably connected to the other end of the band, said latch including spaced side arms and a web portion bridging and joining the same, said side arms having therein, elongated slots which are in laterally opposed relation to each other, said side arms diverging laterally to define a dihedral angle; the length of said T-head being greater than the distance between the side arms in that region of the slots, adjacent the free end of the latch, in which the T-head is received when the band is constricted, and less than the distance between the side arms in the region of the slots remote from said free end, in which remote region the head may be inserted into or removed from the slots without rotating the T-bolt or tilting it laterally.

3. In a band clamp including a constrictor band, a lathing assembly for releasably connecting the opposite ends of the band, said latching assembly comprising: a

' T-bolt adjustably connected to one end of the band; a

latch including a web portion and side arms having more widely spaced ends pivotally attached to the other end of the band, said latch having a free end toward which said arms converge, said arms being integral with the web portion, disposed in laterally spaced opposition, and having respective elongated slots therein, said T-head being longer than the distance between the side arms in that region of the slots adjacent said free end, in which the head is received when the assembly is latched, and being shorter than the distance between the slide arms in another region of the slots, in which other region the head may be freely inserted into or removed from the slots, the ends of the head projecting entirely through their respective slots when the assembly is latched, and said ends engaging the ends of the slots adjacent said free end of the latch, to establish a tension load bearing connection between the T-bolt and the latch.

4. In a band clamp including a constrictor band, a latching assembly for releasably connecting the opposite ends of the band, said latching assembly comprising: a T-bolt having a shank and a T-head transverse to the shank at one end thereof, said shank being adjustably connected to one end of the band and lying generally in the circumferential median plane of the band; and a latch comprising side arms having relatively widely spaced ends swingably connected to the other end of the band, the opposite end of the latch being a free end, said side arms being normal to the common plane of their longitudinal axes and convergent toward said free end in said plane, means bridging and joining said side arms at said free end, said side arms having respective elongated slots with the axis of elongation of each slot generally parallel to said common plane, the ends of the T-head projecting through the respective slots at the free end of the latch when the assembly is latched and the ends of the bolt head clearing the inner faces of the side arms in the region of said walls near said widely spaced ends thereof.

5. A latching assembly comprising: a T-bolt having a shank and a T-head transverse to the shank; and a latch bracket of stamped sheet metal including a pair of laterally spaced side arms substantially normal to the common plane of their longitudinal axes, and a web, bridging and integrally joining said side arms; said side arms having means for pivotally attaching one end of the latch to a member to be latched, the other end of the latch being a free end, said arms converging toward said free end of the latch and having respective elongated slots therein; the bolt head being longer than the internal distance between the side arms in a region of the slots near said free end of the latch and being shorter than the internal distance between the side arms in a region of the slots nearer said one end of the latch, the ends of the head projecting through the respective slots in said free end region when the assembly is latched.

6. A latching device as set forth in claim 5 wherein the web is of limited area confined to the ends of the arms of the free end of the latch, and lies in a plane transverse to said common plane.

7. A latching device as set forth in claim 5 wherein the web integrally joins the side arms along the major portion of the length of their outer longitudinal margins and wherein the under surface of the web is disposed substantially in the common plane of the upper longitudinal margins of the slots.

8. In a band clamp including a constrictor band, a latching assembly for releasably connecting the opposite ends of the band, comprising: a T-bolt having a shank and a transverse T-head, said shank being adjustably connected to one end of the band; a latch including side arms generally normal to the common plane of their longitudinal axes and divergent in that common plane so as to be relatively closely spaced toward the free end of the latch and more widely spaced toward the other end of the latch, a pintle extending transversely between and secured at its respective ends to said side arms at said other end of the latch, the other end of the band having a portion looped around said pintle to provide a swingable connection between said latch and the band, and means providing a rigid transverse bridging connection between said side arms in a region spaced from said pintle toward said free end of the latch, said arms having therein respective elongated slots extending generally parallel to said common plane in the divergent portions of said arms, said T-head being shorter than the maximum distance between the inner faces of said arms, whereby the ends of said T-head may clear said faces to allow said T-head to be readily inserted into said slots or removed therefrom, and said T-head being longer than the minimum distance between said faces, whereby said T-head may engage the said arms at the ends of said slots adjacent said one end of the latch, with the ends of said T-head projecting through the respective slots and locked therein by the pull of said T-bolt derived from tension in said band.

9. A band clamp as defined in claim 8, wherein said common plane of the latch arm axes is normal to the circumferential median plane of said band and substantially tangent to the band, and wherein the divergent portions of said arms define a dihedral angle which is bisected by said median plane of the band, said transverse bridging connection comprising a generally semicylindn'cal web tangent to and integrally joining the side arms of said free end of the latch, the latch being of generally triangular closed loop form.

10. A band clamp as defined in claim 8, wherein said common plane of the latch arm axes is normal to the circumferential median plane of said band and substantially tangent to the band, and wherein the divergent portions of said arms define a dihedral angle which is bisected by said median plane of the band, said latch being of channel section form, with said transverse bridging connection comprising a web joining the outer longitudinal edges of said arms and said slots having their outer longitudinal margins lying in the plane of the inner face of said web, whereby the web functions as a guide to facilitate the insertion of said T-head into said slots.

11. A band clamp as defined in claim 8, wherein said side arms include, adjacent said one end of the latch, portions which are substantially parallel and spaced for close embracement of the T-bolt shank, said bridging connection comprising a web integrally joining said substantially parallel portions in a plane at right angles to said common plane.

12. A band clamp as defined in claim 8, wherein said side arms include, adjacent said one end of the latch, portions which are substantially parallel and spaced for close embracement of the T-bolt shank, and wherein said bridging connection comprises a web integrally joining outerlongitudinal edges of said substantially parallel arm portions and substantially coextensive therewith longitudinally of the latch.

References Cited in the file of this patent UNITED STATES PATENTS 991,769 Catelain May 9, 1911 1,547,065 Noble July 21, 1925 FOREIGN PATENTS 704,299 France Feb. 17, 1931 

